Effect of dielectric barrier discharge plasma, ultra-sonication, and thermal processing on the rheological and functional properties of sugarcane juice.

The present work was designed to study the impact of dielectric barrier discharge (DBD) plasma, ultrasound (US), and thermal treatment on the functional, rheological, and microbial analysis of sugarcane juice. The results showed that plasma and US treatment did not significantly affect the pH and color of the juice. Total soluble solids (°Brix) value increased from 16.30 ± 0.10 for untreated to 20.50 ± 0.15 during plasma treatment at 45 V for 2 min and 16.65 ± 0.27 during US treatment (40 kHz, power 240 W, and time 40 min). The maximum increase of 25% in total phenolic contents (TPC) and 21% in total flavonoid contents (TFC) was observed in a plasma-treated sample at 40 and 45 V (for 2 min) respectively, whereas 18% in TPC and 16% TFC was observed in the US-treated sample (40 kHz, power 240 W, and time 30 min) as compared to control sample. Plasma treatment increased the antioxidant activities (Ferric reducing antioxidant power (FRAP) assay and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) activity) toward maximum at 40 V and only 6% of vitamin C was degraded than others. Similarly, plasma treatment significantly reduced particle size, which further led to decreased significantly (P < 0.05) the apparent viscosity of sugarcane juice with a rise in shear rate and drove to a speedy breakdown on initial shearing. A significant reduction was observed in the microbial load among all treatments as compared to the control. Significant reductions of 3.6 and 0.50 log CFU/mL were observed in the total aerobic mesophilic and yeast and mold counts after DBD plasma treatment at 45 V for 2 min, respectively. Thus, we can conclude that novel technology like plasma treatment can be effectively used at an industrial scale for the preservation and processing of sugarcane juice. PRACTICAL APPLICATION: Nowadays, novel processing techniques are employed to improve the nutritional quality and stability of juices. The consequences of the present research showed that DBD plasma treatment could improve the TPC, TFC, antioxidant activities, vitamin C, and rheological properties while reducing the activity of the microbial load better than the US and thermal treatment. The verdicts described that novel processing methods can enhance the quality of sugarcane juice at an industrial scale.